/**
 * ***************************************************************************** Copyright (c) 2007,
 * 2008 IBM Corporation and others. All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0 which accompanies this
 * distribution, and is available at http://www.eclipse.org/legal/epl-v10.html
 *
 * <p>Contributors: IBM Corporation - initial API and implementation
 * *****************************************************************************
 */
package org.eclipse.ltk.internal.core.refactoring.resource;

import org.eclipse.core.resources.IResource;
import org.eclipse.core.runtime.CoreException;
import org.eclipse.core.runtime.IProgressMonitor;
import org.eclipse.core.runtime.IStatus;
import org.eclipse.core.runtime.OperationCanceledException;
import org.eclipse.core.runtime.Status;
import org.eclipse.core.runtime.SubProgressMonitor;
import org.eclipse.ltk.core.refactoring.Change;
import org.eclipse.ltk.core.refactoring.RefactoringStatus;
import org.eclipse.ltk.core.refactoring.resource.DeleteResourceChange;
import org.eclipse.ltk.core.refactoring.resource.ResourceChange;
import org.eclipse.ltk.internal.core.refactoring.BasicElementLabels;
import org.eclipse.ltk.internal.core.refactoring.Messages;
import org.eclipse.ltk.internal.core.refactoring.RefactoringCoreMessages;
import org.eclipse.ltk.internal.core.refactoring.RefactoringCorePlugin;
import org.eclipse.ltk.internal.core.refactoring.resource.undostates.ResourceUndoState;

/**
 * Undo a resource delete change. This uses the {@link ResourceUndoState} to reverse the change.
 *
 * @since 3.4
 */
public class UndoDeleteResourceChange extends Change {

  private final ResourceUndoState fResourceState;

  public UndoDeleteResourceChange(ResourceUndoState resourceDescription) {
    fResourceState = resourceDescription;
  }

  public void initializeValidationData(IProgressMonitor pm) {}

  public Object getModifiedElement() {
    return null;
  }

  public String getName() {
    return Messages.format(
        RefactoringCoreMessages.UndoDeleteResourceChange_change_name,
        BasicElementLabels.getResourceName(fResourceState.getName()));
  }

  public RefactoringStatus isValid(IProgressMonitor pm)
      throws CoreException, OperationCanceledException {
    if (!fResourceState.isValid()) {
      return RefactoringStatus.createFatalErrorStatus(
          Messages.format(
              RefactoringCoreMessages.UndoDeleteResourceChange_cannot_restore,
              BasicElementLabels.getResourceName(fResourceState.getName())));
    }
    return new RefactoringStatus();
  }

  public Change perform(IProgressMonitor pm) throws CoreException {
    if (fResourceState.verifyExistence(true)) {
      String message =
          Messages.format(
              RefactoringCoreMessages.UndoDeleteResourceChange_already_exists,
              BasicElementLabels.getResourceName(fResourceState.getName()));
      throw new CoreException(
          new Status(IStatus.ERROR, RefactoringCorePlugin.getPluginId(), message));
    }

    IResource created = fResourceState.createResource(pm);
    created.refreshLocal(IResource.DEPTH_INFINITE, new SubProgressMonitor(pm, 1));
    DeleteResourceChange change = new DeleteResourceChange(created.getFullPath(), true, false);
    change.setValidationMethod(
        ResourceChange.VALIDATE_NOT_READ_ONLY | ResourceChange.VALIDATE_NOT_DIRTY);
    return change;
  }

  public String toString() {
    return Messages.format(
        RefactoringCoreMessages.UndoDeleteResourceChange_revert_resource, fResourceState.getName());
  }
}
